188 DEATH OF THE TREE FOUNDED ON 



put forth are too enfeebled in their vitality to produce 

 buds, their axils remaining unfruitful, and all further rami- 

 fication is thus necessarily arrested. 



It is the nature of all living organisms, whether animal 

 or vegetable, to be running through one perpetually recur- 

 ring cycle of the same life-changes, of infancy, maturity, 

 decay, and dissolution. The compound plant called a tree, 

 is no exception to this universal law of Nature. We have 

 seen that, in the earlier portions of its life, it is represented 

 by each of its parts. These parts do not all die at the 

 same time, and their individuality is strikingly indicated 

 by their different periods of life. Thus, the cells of the 

 wood and bark, together with the different varieties of leaf- 

 forms, called by Botanists bud-scales, stipules, bracts, sepals, 

 petals, stamens, and pistils, have all a life peculiar to them- 

 selves. The bu^-scales have arrived at the close of life 

 when the green leaves of the stem are in their infancy, and 

 in spring make their appearance, and throw off their winter 

 envelopes ; and the petals and stamens die when the pistils 

 begin to mature. Even the vitality of the walls of the 

 ovary, or seed-vessel itself, is exhausted in the formation 

 of the seed, and dies after nourishing into life the embryo 

 plant which is contained within its folds. 



Not only the leaves, but the shoots, branches, and 

 branchlets, arrive at their maximum development, and 

 then manifest all the symptoms of a gradually expiring 

 vitality ; and this, too, at different periods of time. It is 

 not always that leaves form buds, or buds become mother- 

 shoots or branches. The leaves situated towards the upper 

 part of the shoot usually form the finest buds ; and from 

 these shoots proceed, which develope other shoots, at their 

 sides and summits, and thus become mother-shoots or 

 branches; and these branches develope another genera- 

 tion of shoots or branchlets ; and so on, until the vital 

 powers of the branch are exhausted, which happens some- 

 times in the second, third, and occasionally in the fourth 

 generation. But the buds produced by the under leaves 

 either form rudimentary shoots, or mere clusters of leaves ; 



